Help - Duplicate Songs on iPhone but not iTunes

Intersting problem. I purchased 4 albums last night on iTunes. I started to download them over wi-fi directly to the phone but then a long music vid was over 20 MB and I had to switch over to downloading from my laptop which was not immediately at hand at the time.
Once I had done this and synced everything up three of the albums have duplicate tracks, including one that duplicated every track - on the phone, not in iTunes.
I have searched the net, these forums etc an 'show duplicate tracks' on the file menu is not helpful as my iTunes doesn't have any duplicate tracks other than other versions of the same song ie: live vs. studio.
I went into my iTunes music folder on my 'puter's hard drive and again, no duplicates there.
I even considered a restore but then was stopped when a dialogue box came up saying that I had purchased items on the iPhone that had not been transferred to iTunes yet when I click on that option iTunes runs a sync nothing changes.
Any ideas? I know that there is no way to delete songs from the iPhone directly. There are no duplicates in any folders to deal with. It may seem like a small thing but I don't care how good an album is, I don't want to hear every song twice. Ya, I know, I could just skip to the next track but what can I say, I like things to be the way they are supposed to be. Any help appreciated. Thanks.

I bought them on my phone & started downloading. Then the larger vid file over 20 mb couldn't be downloaded over so I switched over to the laptop on iTunes and continued d/l'ing there. That's probably what screwed things up. Thanks again.